A New Era in Stretchable Electronics

In Brief

Soft Robots

Scientists from Cornell University and the Italian Technology Institute in Pontedera have developed an elastic robotic skin that is able to stretch up to five times its size, change colors, and even detect pressure.

The luminescent skin, partly funded by the Army and Air Force’s research wings, is comprised of different kinds of specialized silicone, making it flexible and soft.

In the future, it could be used in a host of wearable consumer technologies (yes, your future smartwatch might have elastic, conductive octopus skin). It could also be used to help robots have new forms of camouflage, as the skin allows soft robots to make themselves more or less visible in their environment, adapting as necessary. The robots could also colorize themselves to appear more friendly or aggressive.

Robert Shepherd, a roboticist from Cornell University, adds that these soft robots could also help improve humans’ interactions with robots “because they’re much safer and feel nice” (after all, who wants to cuddle up next to a piece of sharp metal?).

Silicone Layers

The skin’s composition is broken down into three main layers, all of which are made of silicone that has been slightly tweaked. This layered structure allows the skin to be completely flexible, and also what allows it to stretch up to five times its size.

Mechanical engineer Bryan Peele explains: “Starting with the middle layer, basically we took some simple phosphorescent powders (which have been in car dashboards since the ’50s) and mixed them into silicone, so that under a high electric field the material would glow.”

This layer is what allows the skin to glow and change colors by introducing different elements, like copper to make it blue or magnesium to make it yellow.

He continues by outlining how the tech gets its energy: “To power it we need to sandwich it between another material that’s [electrically] conductive, able to stretch, and is also transparent enough to let the glowing layer’s light through.”

For this, the team turned to a technology developed by Harvard researchers in just the past few years: A silicone hydrogel material.

Of course, the two materials are running at a really high voltage, as such, the team notes that you need an insulating outside layer of silicone. This allows you to pull and stretch the material with your hands without the risk of injury and harm. Here, they used stretchy but tough silicone.

Together, these three layers make up the glowing robotic octopus skin.

There are still some kinks that need to be worked out. Another researcher, Chris Larson, notes that in hot, dry environments this material can dry out. But the entire team remains incredibly excited about the technology and its potential. And I, for one, welcome our new robotic octopus skin.